DE1007771B - Process for the production of fluorinated alcohols, aldehydes and saturated hydrocarbons - Google Patents

Description

Process for the preparation of fluorinated alcohols, aldehydes and saturated hydrocarbons When treating unsaturated compounds with Carbon oxide and hydrogen under elevated pressure and at elevated temperature in the presence of catalysts derived from metals of the iron group arise in in many cases oxygen-containing products, especially aldehydes and their corresponding, alcohols formed to some extent under the reaction conditions. The most effective Catalyst is cobalt, which is available as a metal or as a salt of an inorganic or organic Acid is used and is present as a carbonyl compound during the reaction. Before the scope of the new process was explored, many became unsaturated Compounds considered suitable for this implementation, without being in many cases Attempts about it were submitted. This is how unsaturated halogen-containing compounds became mentioned as starting materials for the reaction with carbon monoxide and hydrogen, without that examples were given of their suitability. Later investigations did, however show that unsaturated halogen compounds do not react in the desired sense.

When treating unsaturated halogen compounds containing the halogen carry on a non-multiply bonded carbon atom, with stoichiometric Amount of nickel carbonyl, halogen is split off in the sense of the Wurtz reaction (See U.S. Patent 2,524,833).

The reaction of halogenated benzenes with carbonyls of the iron group and compounds with mobile hydrogen give carboxylic acid derivatives; so arises from p-dichlorobenzene, Ni (CO) 4 and methanol terephthalic acid dimethyl ester (cf. USA patent 2,565,462). Vinyl chloride and its homologues, in which the chlorine is on one double bonded carbon atoms react in the same way.

The implementation of unsaturated halogen compounds with carbon monoxide and hydrogen in the presence of iron group catalysts which convert to aldehydes or leads to alcohols under vigorous conditions has not yet been successful (cf. C. Schuster, Fortschr. chem. Forsch., Vol. 2, 1951, p. 318, H. Adkins, G. Krsek, J. Amer.

Chem. Soc., Vol. 71, 1949, p. 3052).

There are already aromatic fluorine-containing alcohols among the The conditions otherwise used in the oxo synthesis had been heated, but this occurred no addition of water gas analogous to the oxo synthesis.

It is also already a process for the production of trifluoroethyl alcohol described after having ß, ß, P-trifluoroethyl chloride with alkali acetates in the presence or the absence of solvents at at least 200 ° under pressure and the trifluoroethyl acetate obtained is saponified with alkali. This method however, it is carried out in several stages.

Furthermore, it is already known to use fluorinated alcohols by reduction of acid derivatives with lithium aluminum hydride or by reducing fluoroketones in Presence of platinum or palladium catalysts or due to the addition of Grignard compounds to produce fluorinated ketones or fluorinated esters. The raw materials for however, these reactions are quite difficult to produce. In addition, is the hydrolytic splitting off of chlorine or bromine from highly fluorinated organic compounds Strong base connections difficult, as in the same reference also running. A conversion of fluorine-containing olefins into fluorinated alcohols is not yet known, however.

It has now been found that fluorinated alcohols, aldehydes and saturated hydrocarbons from olefins cycloolefins, which apart from fluorine no other Contain halogen atom, can be produced by these with carbon oxide and Hydrogen in the presence of cobalt catalysts at temperatures above 100 "and Pressures above 50 at, optionally with the addition of inert solvents, implemented.

This reaction succeeds with only fluorine-containing olefins and cycloolefins with varying yields depending on the conditions. It also succeeds when the Carbon atoms between which the double bond is located carry fluorine atoms themselves.

The temperatures required for implementation are higher than for this reaction is common, and also occur when using preformed cobalt carbonyl over 100 "and preferably around 1800. For this reason, the primary resulting Aldehyde is often almost completely hydrogenated to alcohol.

As a side reaction, there is often considerable hydrogenation of the fluorinated Olefins or cycloolefins to the fluorinated saturated hydrocarbon on, which can be separated in good yield.

A pressure of more than 50 atm, preferably more, is required for implementation than 200 at, required, with carbon oxide and hydrogen expediently in equimolecular Quantities are applied.

Cobalt carbonyl and hydrocarbon-soluble catalysts are particularly suitable Cobalt compounds such as cobalt naphthenate. Also the use of water-soluble salts is possible. Depending on the boiling point of the starting material, the addition of inert Solvents can be advantageous; occasionally difficulties arise because especially the fluorinated hydrocarbons are very azeotropic Tend to mix. The fluorinated paraffins that come from the corresponding fluoroolefins obtained by the process according to the invention develop very strong secondary valence forces; they often have a surprisingly high boiling point.

The fluorinated ones that can be prepared in a simple manner in this novel way Alcohols and fluorinated paraffins have not been part of the synthesis so far been accessible. They should be used as intermediate products.

Example 1 A stirred autoclave with a capacity of 2 liters is filled with 585 g of hexafluorocyclobutene (Bp = + 2 °) and a solution of 6.4 g of Co2 (CO) 8 in 120 cc of benzene, whereupon 60 at hydrogen and 90 at carbon oxide pressed on and stirring and heating turned on will. The reaction begins at 175 °; by reprinting an equimolecular Mixture of carbon oxide and hydrogen, the pressure is kept at 290 atm. the The reaction, which was initially rapid, ended after 5 hours.

The reaction product, 557 g of a dark liquid, is through Distillation separated, with up to 63 ° 470 g, up to 100 ° 14 g and above 100 ° 56 g Distillate can be obtained.

The part boiling below 100 ° is converted into benzene by freezing out separated and careful distillation; the pure fluorocarbon, 1,2-dihydrohexafluorocyclobutane of the formula C4H2F6, shows the following properties: water-white, easily movable, very volatile liquid with a peculiarly intoxicating smell.

Bp = 63 °, fl200 1.298, D240 = 1.5795. Molecular weight calculated: 164, found: 161. This connection is probably the previously unknown trans compound. The cis compound, made by Buxton and Tatlow in J. Chem. Soc. (London), 1954, p. 1177, has a Kp. = 27 °.

The portion that boils over 100 ° becomes very pure in itself Alcohol of the formula C5H4OF6, presumably 1-oxymethyl-2-hydrohexafluorocyclobutane fractional distillation separated; it has the following properties: water-white Liquid with a deafening smell, bp = 140 to 142 ° or bp 12 = 49 °, IzD = 1.3502, D420 = 1.5989. It is presumably a mixture of stereoisomers. the end A uniform p-nitrobenzoate can be added to the reaction mixture with p-nitrobenzoyl chloride split off. It forms tough prisms with a melting point of 85 °.

Example 2 A solution of 180 g vinylidene fluoride and 10 g Co2 (C. °) 8 in 400 g of cumene is in a 21 capacity autoclave after pressing 180 at water gas heated until the reaction occurs at 1200 and 255 at. The pressure will always kept at 235 at. 185 atm of gas are consumed in 2 hours at 140 °. After cooling and letting down, 598 g of a solution of Difluoropropanol, presumably 3,3-Difluoropropanol- (1), obtained in cumene with the refractive index KD ° = 1.4606, and it is analytically determined an alcohol content of 220 / o, which is a yield of 490! o. In the vacuum distillation, 100 g of one are obtained at bp 12 = 28 ° azeotropic mixture of 790j, difluoropropanol and 21 01o cumene obtained; from the Further alcohol is obtained in between. The difluoropropanol is through the Characterized p-nitrobenzoic acid ester, whose yellowish needles melt at 48 °.

C.0 HgO4NF2 calculated ... N = 5.71%, F = 15.50%; found ... N = 5.50%, F = 15.450 / o.

The corresponding difinorpropionaldehyde is produced as a by-product from the precursors obtained, which is separated in the form of its hemihydrate. The hemihydrate crystallizes in white needles and is completely persistent in air. It has a strong smell Propionaldehyde and is light in water and in most organic solvents soluble. The melting point is 81 °. Ether becomes the compound by adding it Obtained from petroleum ether in large hexagonal plates.

(C2H3F2CHO) 2 H20: Calculated: C = 34.96 01o, H = 4.89%, F = 36.87 01o, molecular weight = 206.14; found. C = 34.57, H = 4.88%, F = 36.66%, molecular weight = 204.

The free aldehyde can be removed from the stable hydrate by dehydration with a mixture of phosphorus pentoxide and sulfuric acid as unstable, volatile Obtained substance that distilled over at 25 to 30 ° and very quickly also at low temperatures to an amorphous glassy mass that polymerizes in acids and is completely insoluble in common organic solvents. She softens above 1300 and gradually disappears above 230 ° by depolymerization.

The aldehyde, like the hemihydrate, gives a dinitrophenylhydrazone, which in yellow needles, m.p. = 129 °, crystallized: C9H804N4F2: calculated ... N = 20.44 ° / o, F = 13.86%; found ... N = 20.48%, F = 13.49%.

Example 3 By using a paraffin with a boiling point of 250 to 300C as a solvent instead of cumene according to Example 2 is the same Yield the same difluoropropanol by simple distillation in the pure state obtain. It is a liquid with a peculiarly pleasant odor, which at 101 boils up to 102 °; nD ° = 1.3464.

C3H6OF2: calculated ... C = 37.50010, H = 6.30%, hydroxyl number = 584; found ... C = 37.43%, H = 6.52%, hydroxyl number = 574.

Example 4 An experiment carried out according to Example 3, but in which Instead of vinylidene fluoride - tetrafluoroethylene is used, provides a corresponding Way the also previously unknown tetrafluoropropanol, which according to his Formulation is to be formulated as 2, 2, 3, 3-tetrafluoropropanol- (l). It's a colorless one Liquid with a pleasant odor, boiling at 106 to 107 ° and a refractive index n20 = 1.3200.

For analysis, the p-nitrobenzoic acid ester is produced, which is found in yellowish needles of F. = 47 ° crystallized.

C, 0H704NF4: calculated ... C = 42.71 ° l0, H = 2.52 ° l0, N = 4,980 / 0, F = 27.03%; found ... C = 42.69 ° lo, H = 2.50%, N = 4.80 0! o, F = 27.27 0Jo.

Example 5 A solution of 192 g of vinylidene fluoride in 250 g of benzene after adding 1.25 g of Co2 (C O) g and pressing 180 at of water gas to 140 ° heated. At this temperature, the reaction that can be recognized by the pressure drop occurs, the pressure being kept constant by pushing in a total of 105 at of water gas will. Gas uptake takes 1 hour.

After cooling and letting down the pressure, the reaction mixture is fractionated distilled. After a preliminary run of hydrogenated products, between 70 and 80 ° enters azeotropic mixture from which the hemihydrate of difluoropropionaldehyde (cf. Example 2) crystallized out in white needles.

After the benzene has passed over, a residue of 33 g remains n020 = 1.4895, which consists of condensation products.

Example 6 If you work without a solvent, that arises same hemihydrate of difluoropropionaldehyde: 188 g vinylidene fluoride were with 10 g Co2 (C 0) 8 heated after pressing 160 at water gas, up to 138 ° the Reaction begins and the pressure drops from 225 at to 190 at in 30 minutes. At the Distilling is possible at 93 ° Fraction with a refractive index n200 = 1.3666 over, which soon completely crystallized and after pressing the hemihydrate of the Represents difluoropropionaldehyde.

Example 7 105 g of tetrafluoroethylene are in an autoclave with 10 g Co2 (C O) s and 150 at water gas (cold pressed) heated to 1500 and 1 hour held at this temperature. After cooling down and relaxing, 60g become one taken from dark liquid. The distillation of this liquid results in an intermediate 80 and 1200 boiling fraction, which mainly consists of 2, 2, 3, 3-tetrafluoropropanol- (l) consists. The alcohol is, as stated above, via the p-nitrobenzoic acid ester cleaned. In this way, 30 g of the pure alcohol boiling at 107 ° from Refractive index nD20 = 1.3200 obtained.

Claims (1)

PATENT CLAIM Process for the production of fluorinated alcohols, Aldehydes and saturated hydrocarbons, characterized in that they are fluorinated Olefins or cycloolefins which contain no other halogen atom apart from fluorine, in a manner known per se with carbon oxide and hydrogen in the presence of cobalt catalysts at temperatures above 100 ° and pressures above 50 at, optionally with the addition of inert solvents. References considered: J. Am. Chem. Soc., Vol. 74, 1952, Pp. 4079 to 4084; G. Schiemann, Dieorgan Fluorverbindungen, 1951, p.63; J. H. Simons, Fluorine Chemistry, 1950, pp. 483-485